Deburring and Surface Finishing: Achieving Your Optimum Results

September 30, 2009

Deburring and Surface Finishing: Achieving Your Optimum Results

THE FIRST STEP TOWARD ACHIEVING OPTIMUM RESULTS IS TO MAKE CERTAIN YOU’RE USING THE RIGHT PROCESS, THE RIGHT MEDIA AND THE RIGHT COMPOUND FOR THE JOB. SO WHICH SYSTEM IS THE RIGHT ONE FOR YOU?

Each type of deburring and surface finishing process has particular characteristics and will produce a highly predictable and reproducible result. In order to achieve that best possible result, consider what you’re working with and what you want to achieve when selecting a system.

Barrel Tumbling: This system is best used to remove heavy burrs, round edges or to create quick “safe edges” on stampings, machined or molded parts. As an aggressive deburring method, barrel tumbling is ideal for heavy cutting with abrasives, or to produce a high shine using a polishing media. Barrel tumbling tends to attack edges and round corners more than other surfaces and does not penetrate well into recesses or interior areas of a part.

Vibratory Finishing: For general deburring/finishing, for delicate parts and for precision deburring/finishing this system is the preferred choice. Vibratory finishing is also safest for threaded parts, though it is not as effective as barrel tumbling for rounding edges or removing tough, heavy burrs. Relative to barrel tumbling, the vibratory finishing process results in smoother surfaces. Vibratory tumbling is more desirable for fragile parts or large parts that could be damaged in a barrel tumbler. Vibratory systems can also reduce handling due to easier to loading and unloading.

Sandblasting: Abrasive blasting is best used for very light deburring or scale removal and to provide an even finish for painting or plating. Using a high-pressure air stream, sandblasting propels abrasives against the minutest details to produce a very even finish. The finish provided by sandblasting can range from a very smooth, satin-like finish with glass beads to a rough, etched surface with aluminum oxide. Abrasive blasting is a dry process and eliminates much of the cleaning required after barrel or vibratory tumbling, which is typically a wet process.

NOW IT’S TIME TO CHOOSE THE RIGHT TUMBLING MEDIA.

General burr removal can be performed using ceramic media. Ceramic media ranges from very hard for light deburring or polishing to softer media with more abrasive content for fast cutting. Ceramic media is ideal for hard metals such as steel and titanium. Plastic or Synthetic media is used when a part needs a light deburring with a smooth surface finish, for delicate parts or when harder ceramic media would gouge a soft metal. Hardwood media in a dry tumbling process is used on plastic parts to achieve both deflashing and a very smooth, high polish.

ALL RIGHT, YOU’VE PICKED THE RIGHT SYSTEM, AND THE RIGHT MEDIA. NOW SELECT THE RIGHT COMPOUND.

The compound you use determines how your media will perform. Powder compounds are typically used in barrel tumblers and are designed to keep the process clean, lubricated and the enhance the performance of the media. Liquid compounds are typically used in vibratory tumblers to aid in a smooth interaction between the media and the parts and to provide a smooth and uniform result on the edges and surfaces of the parts. The type of metal or plastic of the part along with the required final finish will determine which compound will product the optimal result. In addition to these benefits, Kramer Industries offers both powder and liquid compounds that contain in-process corrosion inhibitors.